How can I restore iPhone data from an iCloud backup?
Your iPhone data can be restored from iCloud when setting up a new device, or after erasing all data from a device using Settings -> General -> Reset -> Erase All Content and Settings.
You will be prompted by Setup Assistant by a new iPhone to set up as a new phone or restore from backup.
Make sure your iPhone is connected to Wi-Fi and plugged into the charger.
Select the option Restore From iCloud Backup.
Enter your iCloud account and password.
Choose the recent backup you wish to restore to your iPhone.
Enter any passwords required when prompted.
You will see a progress bar with time remaining as iCloud restores your data. When this is complete, iCloud will begin to download apps. You will see a progress bar under apps that are being downloaded. If you need a specific app first, tap its icon to move it ahead in the queue. To check if the restore is finished, navigate to Settings -> iCloud -> Storage & Backup.
iTunes Match users can download albums, playlists and songs from iCloud when the restore is finished.